Trips in pos, value bet river?

[Chicago Twister]

The theme for my session tonight was 'trips all round'. Not well known opponent, but I can see a little spittle on his shirt, so he might be a drooler.

Full Tilt Poker - No Limit Hold'em Cash Game - $0.25/$0.50 Blinds - 6 Players - (LegoPoker Hand History Converter)

SB: $49.50
BB: $50.00
UTG: $80.75
MP: $91.15
CO: $20.45
Hero (BTN): $64.05

Preflop: Hero is dealt K[img]/images/graemlins/spade.gif[/img] Q[img]/images/graemlins/spade.gif[/img] (6 Players)
UTG calls $0.50, MP calls $0.50, CO folds, <font color="red">Hero raises to $3.00</font>, 2 folds, UTG calls $2.50, MP calls $2.50

Flop: ($9.75) Q[img]/images/graemlins/heart.gif[/img] 2[img]/images/graemlins/diamond.gif[/img] Q[img]/images/graemlins/diamond.gif[/img] (3 Players)
UTG checks, MP checks, <font color="red">Hero bets $6.00</font>, UTG folds, MP calls $6.00

Turn: ($21.75) 4[img]/images/graemlins/club.gif[/img] (2 Players)
MP checks, <font color="red">Hero bets $15.00</font>, MP calls $15.00

River: ($51.75) T[img]/images/graemlins/club.gif[/img] (2 Players)
MP checks, Hero ... ?

Value bet?